* fix(browser): stop new MCP browser tabs stealing focus
browser_new_tab used openTabFocused, switching the workspace UI to
the new tab and interrupting whatever the user was looking at.
Automation commands don't need visual focus to work: webviews stay
resident and paintable regardless, so open the tab in the background
via openTabInBackground instead.
* fix(browser): stop background MCP tabs hijacking Reload
openBrowserTabForRequest still called setWorkspaceActiveBrowser for
tabs opened in the background, so the desktop Reload/Force Reload
menu (which targets getMostRecentWorkspaceActivePaseoBrowserWebContents)
could reload an agent's hidden tab instead of whatever the user was
looking at. Automation commands never needed this: every tab-scoped
MCP tool takes an explicit browserId, and the existing
useSyncWorkspaceActiveBrowser hook already keeps "active browser" in
sync with real UI focus. Drop the redundant call.
